Sparktank, thanks so much for your reply! =) It has been extremely helpful, and I'm sure will continue to be very helpful as I continue with putting together my edit! Hopefully will have something to show relatively soon, thanks to your post!

I have noticed that sometimes when importing an MP4 into Sony Vegas that it has set up6 audio channels already; although one slight issue I've had with MP4's is video and audio being out of sync; I'm presuming it's a pretty simple fix in properties tab of one of them to get them back synced, but google and youtube has yet to reveal an answer.